The Hochiki ALN-V Photoelectric Smoke Sensor is particularly suited to detecting optically dense smoke typical of fires involving materials such as soft furnishings, plastic, foam or other similar materials which tend to smolder and produce large visible smoke particles.
Features

• Low profile – only 2.00″ high, including base
• Simple and reliable device addressing
• Automatic compensation for sensor contamination
• Built-in fire test feature
• Uses the noise-immune Digital Communication Protocol (DCP), which utilizes interrupts for fast response to fires
• Two built-in power/alarm LEDs
• Programmable non-polling LEDs
• Non-directional smoke chamber
• Vandal resistant security locking feature